This invention relates to joining tools and processes and more particularly to tools and processes for explosive joining of tubes.
Demand is increasing for highly reliable, remote, metal joining processes for hazardous or inaccessible operations such as nuclear reactor repairs or assembly of structures in space. Prior art methods, such as mechanical fasteners, swaging fusion welding, soldering and adhesives have been inadequate due to constraints to hand operations, excessive downtime of the mechanism, inaccessibility of the parts to be joined, insufficient strength, resistance to environments (particularly high temperatures) and other constraints. Only explosive joining offers the characteristics to meet the above requirements. This type of joining produces metallurgical bonds which are impossible to achieve by any other processes. The explosive joining process produces a high velocity, angular collision between the metal surfaces which causes interactomic, electron-sharing linkups to be formed. However, previous methods of explosive joining have had limited suitability due to the necessity of using relatively large amounts of explosive which results in a lack of ability to precisely locate the joint and probable damage to lightweight structures such as small tubes and thin tube plates.
Accordingly, it is an object of the present invention to provide a means of explosive joining which minimizes the amount of explosive required.
Another object of the present invention is to provide a means of explosive joining which allows precise location of the joint.
Yet another object of the present invention is to provide a means of explosive joining which reduces damaging pressure waves, noise nuisance and damage to surrounding structures.
A further object of the present invention is to provide a tool capable of holding an explosive joining means in contact with the internal surface of a tube to be joined.
Still another object of the present invention is to provide a method of explosive joining which uses safe, prepackaged joining devices which are storable and which can be mechanized for use without human contact.